Cord blood bilirubin as a predictor for neonatal hyperbilirubinemia in term and late preterm neonates

Objectives: The most frequent reason for readmission in the early neonatal period is hyperbilirubinemia. For economic reasons, the early discharge of healthy term newborns after delivery has been a frequent practice. The objective was to assess the accuracy of cord blood bilirubin in predicting hyperbilirubinemia in newborns ≥35 weeks at 48–72 h of life and to compare the transcutaneous bilirubin levels’ accuracy with total serum bilirubin levels in late preterm and term neonates between 48 and 72 h of life. Material and Methods: A prospective observational study was carried out on 60 neonates, ≥35 weeks, delivered in the A J Institute of Medical Sciences and Hospital during the period from February 2021 to August 2022. Cord blood bilirubin levels are checked at birth and serum bilirubin levels and transcutaneous bilirubin levels are checked in babies who develop clinical icterus at 48–72 h of life. Results: Among 60 neonates included in the study, 40 (66.7%) were male and 20 (33.3%) were female. Among them, 51 (85%) were term and 9 (15%) were late preterm neonates. We performed a receiver operator characteristic curve analysis to find a cutoff point level of cord blood bilirubin for the development of significant hyperbilirubinemia. Cord bilirubin levels cutoff was 2.25 ± 0.476 mg/dL, with a sensitivity of 60%, specificity of 67%, positive predictive value of 89.1% and negative predictive value of 27.15%, with an area under the curve of 0.61; hence, we can use cord blood bilirubin as a good predictor for neonatal hyperbilirubinemia. Transcutaneous bilirubin meter (BiliCare) showed positive correlation with serum bilirubin levels at 48–72 h (r = +0.963, P < 0.001 in term and r= + 0.872, P < 0.01 in late preterm). Conclusion: In the present study, a cutoff value of ≥2.25 mg/dL for cord blood bilirubin had a sensitivity of 60%, a specificity of 67% and an area under the curve of 0.61 to predict hyperbilirubinemia at 48–72 h of life. As a result, it can be utilised as a reliable predictor for neonatal hyperbilirubinemia and to make plans for early discharge. Transcutaneous bilirubin meter (BiliCare) showed positive correlation with serum bilirubin levels in term and late preterm; hence, we can use this instrument to check hyperbilirubinemia at 48–72 h of life so that pricking for blood sampling can be avoided.